gsub

问题 We want to extract parameters and values from a given URL like http://www.exemple.com/?a=1&b=2&c=3#def Using xml2::url_parse we were able to Parse a url into its component pieces. However we still want to devide the query into elements using gsub matching regular expression: ([^?&=#]+)=([^&#]*) Desired output a=1 b=2 c=3 回答1: We can try library(stringr) matrix(str_extract_all(str1, "[a-z](?=\\=)|(?<=\\=)\\d+")[[1]], ncol=2, byrow=TRUE) Or if we need the = also str_extract_all(str1, "[a-z]=\\d

问题 Breaking up the below code to understand my regex and gsub understanding: str = "abc/def/ghi.rb" str = str.gsub(/^.*\//, '') #str = ghi.rb ^ : beginning of the string \/ : escape character for / ^.*\/ : everything from beginning to the last occurrence of / in the string Is my understanding of the expression right? How does .* work exactly? 回答1: Your general understanding is correct. The entire regex will match abc/def/ and String#gsub will replace it with empty string. However, note that

问题 I have text that has these fancy double quotes: '“' and I would like to replace them with regular double quotes using Ruby gsub and regex. Here's an example and what I have so far: sentence = 'This is a quote, “Hey guys!”' I couldn't figure out how to escape double quotes so I tried using 34.chr: sentence.gsub("“",34.chr). This gets me close but leaves a back slash in front of the double quote: sentence.gsub("“",34.chr) => 'This is a quote, \"Hey guys!”' 回答1: The backslashes are only showing

问题 I'm working with a file generated from several different machines that had different locale-settings, so I ended up with a column of a data frame with different writings for the same word: CÓRDOBA CÓRDOBA CÒRDOBA I'd like to convert all those to CORDOBA . I've tried doing t<-gsub("Ó|Ó|Ã’|°|°|Ò","O",t,ignore.case = T) # t is the vector of names Wich works until it finds some "invisible" characters: As you can see, I'm not able to see, in R, the additional charater that lies between à and \

问题 This question already has answers here : Replace multiple letters with accents with gsub (11 answers) Closed 6 years ago . I'm currently running the following code to clean my data from accent characters: df <- gsub('Á|Ã', 'A', df) df <- gsub('É|Ê', 'E', df) df <- gsub('Í', 'I', df) df <- gsub('Ó|Õ', 'O', df) df <- gsub('Ú', 'U', df) df <- gsub('Ç', 'C', df) However, I would like to do it in just one line (using another function for it would be ok). How can I do this? 回答1: Try something like

问题 Say I use gsub and want to remove the following (=,+,-) sign from the string and replace with an underscore. Can someone describe what is going on when I try to use the gsub with a plus sign (+). test<- "sandwich=bread-mustard+ketchup" # [1] "sandwich=bread-mustard+ketchup" test<-gsub("-","_",test) # [1] "sandwich=bread_mustard+ketchup" test<-gsub("=","_",test) # [1] "sandwich_bread_mustard+ketchup" test<-gsub("+","_",test) #[1] "_s_a_n_d_w_i_c_h___b_r_e_a_d___m_u_s_t_a_r_d_+_k_e_t_c_h_u_p_"

问题 I observe the following character: l <- "mod, range1 = seq(-m, n, 0.1), range2 = seq(-2, 2, 0.1), range3 = seq(-2, 2, 0.1)" Using regular expressions in R I desire to split l in the following structure: [1] "mod" "range1 = seq(-m, n, 0.1)" [3] "range2 = seq(-2, 2, 0.1)" "range3 = seq(-2, 2, 0.1)" Unfortunetely, I didn't find a proper way to overcome the problem, yet. Anyone has an idea how is it possible to acquire such an elegeant split? 回答1: I really doubt you can do it with regular

问题 I'm trying to create permalink like behavior for some article titles and i don't want to add a new db field for permalink. So i decided to write a helper that will convert my article title from: " O "focoasă" a pornit cruciada, împotriva bărbaţilor zgârciţi " to " o-focoasa-a-pornit-cruciada-impotriva-barbatilor-zgarciti ". While i figured out how to replace spaces with hyphens and remove other special characters (other than -) using: title.gsub(/\s/, "-").gsub(/[^\w-]/, '').downcase I am

问题 I am using gsub in R to add text into the middle of a string. It works perfectly but for some reason, when the location gets too long it throws an error. The code is below: gsub(paste0('^(.{', as.integer(loc[1])-1, '})(.+)$'), new_cols, sql) Error in gsub(paste0("^(.{273})(.+)$"), new_cols, sql) : invalid regular expression '^(.{273})(.+)$', reason 'Invalid contents of {}' This code works fine when the number in the brackets(273 in this case) is less but not when it is this large. This

问题 I would like to recode some identifiers, from upper case to lower case. I am not sure what the issue is here. n = c('AFD.434', 'BSD.23', 'F234.FF') gsub(pattern = '[[:upper:]]', replacement = '[[:lower:]]', n) [1] "[[:lower:]][[:lower:]][[:lower:]].434" "[[:lower:]][[:lower:]][[:lower:]].23" "[[:lower:]]234.[[:lower:]][[:lower:]]" Any advice? 回答1: Your gsub call replaces each occurrence with the literal string "[[:lower:]]". The simplest solution is to not use regular expressions; simply use